Daryll M. LaCourse
A5018888019- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- History and Developments in Astronomy
- Calibration and Measurement Techniques
- Astrophysics and Cosmic Phenomena
- Adaptive optics and wavefront sensing
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Inertial Sensor and Navigation
- Atmospheric Ozone and Climate
- Space Exploration and Technology
- Radioactive Decay and Measurement Techniques
- Species Distribution and Climate Change
Bellevue Hospital Center
2021
Yale University
2013-2015
ABSTRACT The primary Kepler Mission provided nearly continuous monitoring of ∼200,000 objects with unprecedented photometric precision. We present the final catalog eclipsing binary systems within 105 deg 2 field view. This release incorporates full extent data from mission (Q0-Q17 Data Release). As a result, new have been added, additional false positives removed, ephemerides and principal parameters recomputed, classifications revised to rely on analytical models, eclipse timing variations...
Over the duration of Kepler mission, KIC8462852 was observed to undergo irregularly shaped, aperiodic dips in flux up $\sim 20$\%. The dipping activity can last for between 5 and 80 days. We characterize object with high-resolution spectroscopy, spectral energy distribution fitting, radial velocity measurements, imaging, Fourier analyses light curve. determine that is a typical main-sequence F3 V star exhibits no significant IR excess, has very close interacting companions. In this paper, we...
ABSTRACT Studying the properties of young planetary systems can shed light on how dynamics and structure planets evolve during their most formative years. Recent K 2 observations nearby clusters (10–800 Myr) have facilitated discovery such systems. Here we report a Neptune-sized planet transiting an M4.5 dwarf (K2-25) in Hyades cluster (650–800 Myr). The curve shows strong periodic signal at 1.88 days, which attribute to spot coverage rotation. We confirm that host is member by measuring...
In this paper we present a catalog of 4584 eclipsing binaries observed during the first two years (26 sectors) TESS survey. We discuss selection criteria for binary candidates, detection hither-to unknown systems, determination ephemerides, validation and triage process, derivation heuristic estimates ephemerides. Instead keeping to widely used discrete classes, propose star morphology classification based on dimensionality reduction algorithm. Finally, statistical properties sample,...
ABSTRACT We present ten young (≲10 Myr) late-K and M dwarf stars observed in K2 Campaign 2 that host protoplanetary disks exhibit quasi-periodic or aperiodic dimming events. Their optical light curves show ∼10–20 dips flux over the 80-day observing campaign with durations of ∼0.5–2 days depths up to ∼40%. These are all members ρ Ophiuchus (∼1 Upper Scorpius (∼10 star-forming regions. To investigate nature these “dippers” we obtained: near-infrared spectra determine stellar properties...
We present the first good evidence for exocomet transits of a host star in continuum light data from Kepler mission. The question, KIC 3542116, is spectral type F2V and quite bright at Kp = 10. have distinct asymmetric shape with steeper ingress slower egress that can be ascribed to objects trailing dust tail passing over stellar disc. There are three deeper depths ≃ 0.1 per cent last about day, several times more shallow shorter duration. were found via an exhaustive visual search entire...
Exoplanets can evolve significantly between birth and maturity, as their atmospheres, orbits, structures are shaped by environment. Young planets ($<$1 Gyr) offer an opportunity to probe the critical early stages of this evolution, where fastest. However, most known young orbit prohibitively faint stars. We present discovery two transiting HD 63433 (TOI 1726, TIC 130181866), a Sun-like ($M_*=0.99\pm0.03$) star. Through kinematics, lithium abundance, rotation, we confirm that is member Ursa...
Abstract The so-called dipper stars host circumstellar discs and have optical infrared light curves that exhibit quasi-periodic or aperiodic dimming events consistent with extinction by transiting dusty structures orbiting in the inner disc. Most of proposed mechanisms explaining dips – i.e. occulting disc warps, vortices, forming planetesimals assume nearly edge-on viewing geometries. However, our analysis three known dippers publicly available resolved sub-mm data reveals a range...
In this work we report the discovery and analysis of six new compact triply eclipsing triple star systems found with TESS mission: TICs 37743815, 42565581, 54060695, 178010808, 242132789, 456194776. All these exhibit distinct third body eclipses where inner binary (EB) occults (`tertiary') star, or vice versa. We utilized photometry, archival photometric data, available spectral energy distribution curves (SED) to solve for properties all three stars, as well many orbital elements. describe...
We report the discovery of 14 new transiting planet candidates in Kepler field from Planet Hunters citizen science program. None these overlapped with Objects Interest (KOIs) at time submission. one more addition to six candidate system around KOI-351, making it only seven Kepler. Additionally, KOI-351 bears some resemblance our own solar system, inner five planets ranging Earth mini-Neptune radii and outer being gas giants; however, this is very compact, all orbiting $\lesssim 1$ AU their...
ABSTRACT CO Cam (TIC 160268882) is the second ‘single-sided pulsator’ to be discovered. These are stars where one hemisphere pulsates with a significantly higher amplitude than other side of star. binary star comprised an Am δ Sct primary Teff = 7070 ± 150 K, and spectroscopically undetected G main-sequence secondary The dominant pulsating centred on L1 point. We have modelled spectral energy distribution combined radial velocities, independently TESS light curve velocities. Both these give...
We report the discovery of TOI-2180 b, a 2.8 $M_{\rm J}$ giant planet orbiting slightly evolved G5 host star. This transited only once in Cycle 2 primary Transiting Exoplanet Survey Satellite (TESS) mission. Citizen scientists identified 24 hr single-transit event shortly after data were released, allowing Doppler monitoring campaign with Automated Planet Finder telescope at Lick Observatory to begin promptly. The radial velocity observations refined orbital period b be 260.8$\pm$0.6 days,...
ABSTRACT In this work, we report the independent discovery and analysis of nine new compact triply eclipsing triple star systems found with Transiting Exoplanet Survey Satellite (TESS) mission: TICs 47151245, 81525800, 99013269, 229785001, 276162169, 280883908, 294803663, 332521671, 356324779. Each these exhibits distinct third-body eclipses where third (‘tertiary’) occults inner binary (EB), or vice versa. We utilize a photodynamical TESS photometry, archival photometric data, eclipse...
We report the detection of a Saturn-size exoplanet orbiting HD 332231 (TOI 1456) in light curves from Transiting Exoplanet Survey Satellite (TESS). 332231, an F8 dwarf star with V-band magnitude 8.56, was observed by TESS Sectors 14 and 15. detect single-transit event Sector 15 presearch data conditioning (PDC) curve. obtain spectroscopic follow-up observations Automated Planet Finder, Keck I, SONG telescopes. The orbital period we infer radial velocity (RV) leads to discovery another...
ABSTRACT In this work we report the discovery and analysis of three new triply eclipsing triple star systems found with TESS mission during its observations northern skies: TICs 193993801, 388459317, 52041148. We utilized precision photometry binary eclipses third-body events, ground-based archival follow-up photometric data, eclipse timing variations, spectral energy distributions, as well theoretical evolution tracks in a joint photodynamical to deduce system masses orbital parameters both...
Abstract We present a catalog of 97 uniformly vetted candidates for quadruple star systems. The were identified in TESS full-frame image data from sectors 1–42 through combination machine-learning techniques and visual examination, with major contributions dedicated group citizen scientists. All targets exhibit two sets eclipses different periods, both which pass photocenter tests confirming that the are on target. This outlines statistical properties sample, nearly doubles number known...
Abstract This article presents the history of Visual Survey Group (VSG)—a Professional-Amateur (Pro-Am) collaboration within field astronomy working on data from several space missions (Kepler, K2 and Transiting Exoplanet Satellite). paper covers formation VSG, its survey-methods including most common tools used discoveries made over past decade. So far, group has visually surveyed nearly 10 million light curves authored 69 peer-reviewed papers which mainly focus exoplanets involving...
We report the latest Planet Hunter results, including PH2 b, a Jupiter-size (RPL = 10.12 ± 0.56 R⊕) planet orbiting in habitable zone of solar-type star. b was elevated from candidate status when series false-positive tests yielded 99.9% confidence level that transit events detected around star KIC 12735740 had planetary origin. volunteers have also discovered 42 new candidates Kepler public archive data, which 33 at least 3 transits recorded. Most these orbital periods longer than 100 days...
The census of exoplanets is incomplete for orbital distances larger than 1 AU. Here, we present 41 long-period planet candidates in 38 systems identified by Planet Hunters based on Kepler archival data (Q0–Q17). Among them, 17 exhibit only one transit, 14 have two visible transits, and 10 more three transits. For with estimate their periods transit duration host star properties. majority the this work (75%) that correspond to 1–3 AU from stars. We conduct follow-up imaging spectroscopic...
We present a strongly interacting quadruple system associated with the K2 target EPIC 220204960. The itself is Kp = 12.7 magnitude star at Teff ~ 6100 K which we designate as "B-N" (blue northerly image). host of system, however, 17 composite M-star spectrum, "R-S" (red southerly With 3.2" separation and similar radial velocities photometric distances, 'B-N' likely physically 'R-S', making this quintuple but that incidental to our main claim in 'R-S'. two binaries 'R-S' have orbital periods...
Aims. We have identified nearly a hundred close triply eclipsing hierarchical triple star systems from data taken with the space telescope TESS. These are noteworthy in that we can potentially determine their dynamical and astrophysical parameters high precision. In present paper, report comprehensive study of seven new compact this larger sample: TICs 133771812, 176713425, 185615681, 287756035, 321978218, 323486857, 650024463. Methods. Most for come TESS observations, but two them Gaia...
The original Kepler mission observed and characterized over 2400 eclipsing binaries (EBs) in addition to its prolific exoplanet detections. Despite the mechanical malfunction subsequent non-recovery of two reaction wheels used stabilize instrument, satellite continues collecting data repurposed K2 surveying a series fields along ecliptic plane. Here, we present an analysis first full baseline release: Campaign 0 set. In 7761 light curves have identified total 207 EBs. Of these, 97 are new...
BG Ind is a well studied, bright, nearby binary consisting of pair F stars in 1.46-day orbit. We have discovered the TESS lightcurve for TIC 229804573 (aka Ind) second eclipsing system with 0.53-day. Our subsequent analyses recent and archival ground-based photometric radial velocity data, reveal that two binaries are gravitationally bound 721-day period, moderately eccentric present results joint spectro-photodynamical analysis eclipse timing variation curves both based on lightcurve, data...
Abstract We have discovered a young M star of mass 0.16 M⊙ and radius 0.63 R⊙, likely in the Upper Sco Association, that exhibits only single 80 per cent deep occultation 1-d duration. The has frequent flares low-amplitude rotational modulation, but is otherwise quiet over 160 d cumulative observation during K2 campaigns C2 C15. discuss how such eclipse not possible by one crossing another any binary or higher order stellar system which no transfer occurred. two explanations we are left with...
KIC 9406652 is a remarkable variable star in the Kepler field of view that shows both very rapid oscillations and long term outbursts its light curve. We present an analysis curve over quarters 1–15 new spectroscopy indicates object cataclysmic with orbital period 6.108 hr. However, even stronger signal appears periodogram for shorter 5.753 hr, we argue this corresponds to modulation flux from hot spot region tilted, precessing disk surrounding white dwarf star. preliminary solution radial...